School refusal is a heterogenous problem which typically emerges in adolescence and co-occurs with internalising disorders. A substantial proportion of adolescents do not respond to existing treatment modalities; thus, novel, effective intervention options are needed. Partners in Parenting Plus (PiP+) is a coach-assisted, web-based intervention designed to empower parents to respond to adolescent internalising disorders.

To conduct a process evaluation of PiP+ and identify programme adaptations required to meet the needs of parents of adolescents who refuse school.

Semi-structured interviews were conducted with 14 Australian mothers who had: (a) received the PiP+ programme (not tailored for school refusal) during a prior research trial; and (b) reported that their adolescent was refusing school during their participation in PiP+. Inductive thematic analysis was used to analyse interview transcripts.

Participants were 41–53 years old (M = 47.8) and parenting adolescent children aged 14–17 years (M = 14.9). Three themes illustrated how PiP+ features met or could better meet the needs of parents of adolescents who were refusing school: (a) feeling heard, supported and respected; (b) relevance to me and my context; and (c) seeing positive changes. Participants had favourable views of PiP+, especially coached components. Participants requested programme enhancements to better meet the needs of parents of neurodiverse adolescents and discussed the impact of cumulative help-seeking ‘failures’ on self-efficacy and locus of control.

PiP+ was highly acceptable to the majority of parents navigating the issue of school refusal. This has implications for the enhancement of coach-assisted parenting interventions and the context-specific adaptation of PiP+ for school refusal.

Observational studies indicate a relationship between vitamin D (25-hydroxyvitamin D; 25OHD) deficiency and the development of internalising disorders, especially depression. However, causal inference approaches (e.g. Mendelian randomisation) did not confirm this relationship. Findings from biobehavioural research suggests that new insights are revealed when focusing on psychopathological dimensions rather than on clinical diagnoses. This study provides further evidence on the relationship between 25OHD and the internalising dimension.

This investigation aimed at examining the causality between 25OHD and internalising disorders including a common internalising factor.

We performed a two-sample Mendelian randomisation using genome-wide association study (GWAS) summary data for 25OHD (417 580 participants), major depressive disorder (45 591 cases; 97 674 controls), anxiety (5580 cases; 11 730 controls), post-traumatic stress disorder (12 080 cases; 33 446 controls), panic disorder (2248 cases; 7992 controls), obsessive–compulsive disorder (2688 cases; 7037 controls) and anorexia nervosa (16 992 cases; 55 525 controls). GWAS results of the internalising phenotypes were combined to a common factor representing the internalising dimension. We performed several complementary analyses to reduce the risk of pleiotropy and used a second 25OHD GWAS for replication.

We found no causal relationship between 25OHD and any of the internalising phenotypes studied, nor with the common internalising factor. Several pleiotropy-robust methods corroborated the null association.

Following current transdiagnostic approaches to investigate mental disorders, our results focused on the shared genetic basis between different internalising phenotypes and provide no evidence for an effect of 25OHD on the internalising dimension.

Randomised controlled trials (RCTs) have provided considerable evidence for the short-term efficacy of cognitive behavioural therapy (CBT) in children and adolescents with depressive and anxiety disorders. However, the effectiveness and long-term stability of treatment effects under routine care conditions remain unproven.

This observational study investigates the effectiveness and stability of CBT under routine care conditions within a large sample of clinically referred youth with depressive and anxiety disorders.

Two hundred and twenty former patients (age 6–18 years at start of treatment) underwent a follow-up assessment (follow-up interval: M=5.3 years, SD=2.47). Parent and self-ratings of behavioural and emotional problems were obtained at the beginning and end of treatment and at follow-up. Additionally, at follow-up, a telephone interview and questionnaires exploring other mental symptoms and life satisfaction were administered.

A repeated measures ANOVA yielded statistically significant, medium to large pre– post symptom reductions (ηp 2=.15 to ηp²=.47) and small to medium post-follow-up symptom reductions (ηp²=.03 to ηp²=.19). At follow-up, between 57 and 70% of the sample reported a decrease in different emotional symptoms since the end of treatment, and 80% reported improved life satisfaction.

These findings provide evidence for the effectiveness and stability of treatment effects of CBT in youth with depressive and anxiety disorders under routine care conditions. Due to the lack of a direct control condition and a substantial proportion of missing data, the results must be interpreted with caution.